Remove duplicate weak definition

The weak pragma was assigned twice to the bl2_plat_handle_post_image_load
definition both in plat/common/ and in plat/arm/common/ this was an error as
it should have only have been defined in plat/common

Change-Id: Id85e14c699cb09ed998d1677f2a172e760911918
Signed-off-by: Daniel Boulby <daniel.boulby@arm.com>

plat/arm/common/arm_bl2_setup.c

@@ -44,12 +44,7 @@ CASSERT(BL2_BASE >= (ARM_BL_RAM_BASE + BL1_MEMINFO_OFFSET), assert_bl2_base_over
 #pragma weak bl2_plat_arch_setup
 #pragma weak bl2_plat_sec_mem_layout
 
-#if LOAD_IMAGE_V2
-
-#pragma weak bl2_plat_handle_post_image_load
-
-#else /* LOAD_IMAGE_V2 */
-
+#if !LOAD_IMAGE_V2
 /*******************************************************************************
  * This structure represents the superset of information that is passed to
  * BL31, e.g. while passing control to it from BL2, bl31_params